My home-build HF PA.
The frontview of the almost finished amplifier. ( PA tuning&input tuning scale not yet finished)
The HV section, the separate fuses for the transformers are visible at right lower corner
1 Another view of the finished amplifier.2
The anode current is adjustable at the frontpanel, the meter-scale and other front-panel text is home made with special software made by F5BU called GALVA. It is freeware and downloadable on his website.
I used water-slide decal paper for transferring the printed text on the front and meter scales.
softstart is a must with this size of transformers !
SWR bridge measuring forward & reflected power. It is equipped with an extra output selection relay and a T/R relay.
SWR bridge placed in the amplifier
The some testing and....
.... RF calibrating the SWR bridge and RF power metering
Finally a pic of milling one of the 6 toothwheels, this one is for the input tuning dail lower right on the frontpanel.
Schematic of adjustable bias control; ALC; SWR protection and T/R control
Schematic of power supply.